With their military mission and extensive financial resources, the Knights Templar funded a large number of building projects around Europe and the Holy Land, many of which structures remain standing today.

The port city and fortress of Tartous (called Tortosa by Crusaders), Syria

In 1867, a team from the Royal Engineers, led by Lieutenant Charles Warren (later the London police commissioner of Jack the Ripper fame) and financed by the Palestine Exploration Fund (P.E.F.), discovered a series of tunnels beneath Jerusalem and the Temple Mount, some of which were directly underneath the Templar headquarters. Various small artifacts were found which indicated that Templars had used some of the tunnels, though it is unclear who exactly first dug them. Some of the ruins which Warren discovered came from centuries earlier, and other tunnels which his team discovered had evidently been used for a water system, as they led to a series of cisterns.[1][2][3][4]

France

Sainte-Vaubourg, 76/Seine-Maritime, Haute-Normandie, France. In 1173, King Henry II, gave the manor Sainte-Vaubourg at Val-de-la-Haye to the Knights Templar.

Mont-de-Soissons, 02/Aisne, Picardie, France - The chapel, pigeonniere and grange all date from the XIIIth century. The chapel was restored by the Knights of St. John after the dissolution of the Templars.

Acquebouille, in Outarville, 45/Loiret, France - This chapter-house was part of Commandery Saint-Marc d' Orleans.

The Križanke Monastery Church (Križevniška cerkev) in Ljubljana, Slovenia, located next to the Križanke Summer Theatre , which has also been referred to as the Monastery Church of Our Lady of Mercy, which was build as a part of the Teutonic Knights' building ( a monastery with a church and school) build between the years 1265 and 1270 and was walled in before 1307, replaced the older Knights Templar post (1167- 1200), which was handed over in 1228, to the Teutonic Knights'.